Well, I don't know the ST rates. But the Eibachs are a progressive spring, meaning they are "softer" at the top, but when you puch them hard and they compress more, they get stiffer. Makes for a good ride, but excellent handling when pushed. Rates are as follows (from mfuller):
Front: Progressive; 171#-234#
Rear: Progressive; 87#-143#
Rever to the thread below for more info on spring rates, if you want to know more.
http://invision.aleromod.com/index.php?sho...hl=spring+rates